C dataadapter update not updating database
It's also useful when you get a second dataset from a component such as an XML web service, or when you need to integrate data from multiple datasets.When merging datasets, you can pass a Boolean argument () that tells the Merge method whether to retain existing modifications in the target dataset.If you aren't using data-bound controls, then you have to manually call the Update method of the same Table Adapter (or data adapter) that you used to populate the dataset.However, you can also use different adapters, for example, to move data from one data source to another or to update multiple data sources.After you complete an update, you can re-enable constraint checking, which also re-enables update events and raises them.
For more information, see Validate data in datasets.
This means that if you try to update the original data source with the target dataset, it might not be able to find the original row to update.
You can prevent a concurrency violation by filling another dataset with the updated records from the data source and then performing a merge to prevent a concurrency violation.
When you update a record in a dataset, there is the possibility of an error.
For example, you might inadvertently write data of the wrong type to a column, or data that's too long, or data that has some other integrity problem.